Katy Perry Hears Secret Justin Bieber Song: "It's A Game Changer!"

28 June 2012, 09:36 | Updated: 28 June 2012, 09:55

The 'Boyfriend' singer also congratulated Katy on a "great" movie after attending the premiere of Part Of Me 3D.

Katy Perry says Justin Bieber played her a "game changer" song this week after attending the premiere of her film Part Of Me 3D earlier this week.

The 'California Gurls' singer also thanked 'Boyfriend' star Justin for his message of congratulations, following the successful launch of her first concert movie at the film's premiere in Hollywood on Tuesday (26th June).

"Congrats @katyperry on a great movie. proud of u," Justin tweeted to 'Firework' singer Katy after watching Part Of Me 3D at the event in Los Angeles.

"Thanks dewed," Katy later replied. "I really like that song u played me last night. Game changer!"

View a picture of Katy Perry meeting one of her younger fans at the premiere of Part Of Me 3D this week below (Credit: Getty):

'Never Say Never' singer Justin launched his new album 'Believe' last week and it was announced yesterday that the record has scored the biggest debut of the year after selling 374,000 copies in a single week to place it firmly at the top of the US Billboard Top 200 chart.

Justin also confirmed this week that he will release his Big Sean album collaboration 'As Long As You Love Me' as the second official single to be lifted from 'Believe'.

The star-studded premiere for Katy's new film took place on Tuesday and was attended by Justin alongside the likes of Selena Gomez, Carly Rae Jepsen and Robert Pattinson, and saw Katy walking the event's pink carpet with her 90 year-old grandmother.

Katy Perry's 3D concert movie Part Of Me 3D is due for release in cinemas worldwide on 5th July.